[llvm] [AArch64][CodeGen] Fix crash when fptrunc returns fp16 with +nofp attr (PR #81724)

[David Green via llvm-commits]

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@@ -541,13 +541,18 @@ AArch64TargetLowering::AArch64TargetLowering(const TargetMachine &TM,
   setOperationAction(ISD::STRICT_UINT_TO_FP, MVT::i32, Custom);
   setOperationAction(ISD::STRICT_UINT_TO_FP, MVT::i64, Custom);
   setOperationAction(ISD::STRICT_UINT_TO_FP, MVT::i128, Custom);
-  setOperationAction(ISD::FP_ROUND, MVT::f16, Custom);
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davemgreen wrote:

I think this can be `if (Subtarget->hasFPARMv8()) setOperationAction(ISD::FP_ROUND, MVT::f16, Custom);`

https://github.com/llvm/llvm-project/pull/81724